title: Feasibility of 39-potassium MR imaging of a human brain at 9.4 Tesla.
abstract: OBJECTIVE
  To demonstrate the feasibility of performing 39-potassium MR imaging of a human brain.
  
  
  METHODS
  39-Potassium magnetic resonance imaging of a human brain was performed at 9.4 T using a flexible twisted projection imaging acquisition with a nominal isotropic spatial resolution of 10 mm in 40 min using a single-tuned birdcage radiofrequency coil. Co-registered sodium imaging with a nominal isotropic spatial resolution of 3.5 mm was performed on the same subject in 10 min.
  
  
  RESULTS
  The 39-potassium flexible twisted projection imaging imaging had a signal-to-noise ratio of 5.2 in brain paranchyma. This qualitative imaging showed the expected features when compared to co-registered high- and low-resolution sodium imaging of the same subject.
  
  
  CONCLUSIONS
  Potassium MR images may offer complementary information to that of sodium MR images by sampling the intracellular rather that interstitial environment. Quantification will require additional improvement in signal-to-noise ratio to produce clinically useful bioscales as are developing for sodium MR imaging.
authors.affiliation: Center for Magnetic Resonance Research, University of Illinois, Chicago, Illinois, USA.
authors.forename: Ian C
authors.initials: IC
authors.lastname: Atkinson
authors.forename: Theodore C
authors.initials: TC
authors.lastname: Claiborne
authors.forename: Keith R
authors.initials: KR
authors.lastname: Thulborn
mesh_terms: D001923:Brain Chemistry; D003287:Contrast Media / Q000737:chemistry; D005240:Feasibility Studies; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D011188:Potassium / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014018:Tissue Distribution
chemical_list: D003287:Contrast Media; D011188:Potassium
keywords: 39K MRI; brain. 9.4T; human; potassium MRI; ultrahigh field